* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

li {
    list-style: none;
}

a,
u {
    text-decoration: none;
    color: black;
}

i,
em {
    font-style: normal;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    font-weight: 400;
    font-size: 16px;
}

b,
strong {
    font-weight: 400;
}

input {
    border: none;
    /* 轮廓线 */
    outline: none;
}

/* 万能消除法 */
.clearfix::after {
    content: "";
    display: block;
    width: 0;
    height: 0;
    overflow: hidden;
    visibility: hidden;
    clear: both;
}